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System Name | Silent allround |
---|---|
Processor | i5 750 @ 3,0Ghz 1.04v / 3.4Ghz 1.11v/ 3,6Ghz 1.15v |
Motherboard | Gigabyte P55-USB3 |
Cooling | Thermalright IFX-14 + Scythe Slip Stream 140mm @ 600RPM |
Memory | 2 x 4GB Samsung M378B5273DH0-CH9 @ 2000 MHz 9-10-10-27 T1 |
Video Card(s) | Sapphire HD 5870 Vapor-X @ 940/1270 |
Storage | Intel Postville 80GB SSD & Western Digital Green 2TB |
Display(s) | Dell Ultrasharp U2412M |
Case | Bitfenix Merc Alpha |
Audio Device(s) | Asus Xonar D2 with Unified Drivers |
Power Supply | Nexus NX-5000 R3 530W |
Software | Windows 7 Home Premium x64 |
Benchmark Scores | Super pi 1M : 8,549s @ 4,7Ghz (Core i7 920) |
A solid-state drive (SSD) is a data storage device that uses solid-state memory to store persistent data. An SSD emulates a hard disk drive interface, thus easily replacing it in most applications. An SSD using SRAM or DRAM (instead of flash memory) is often called a RAM-drive, not to be confused with a RAM disk.
The original usage of the term solid-state (from solid-state physics) refers to the use of semiconductor devices rather than electron tubes, but in this context, has been adopted to distinguish solid-state electronics from electromechanical devices as well. With no moving parts, solid-state drives are less fragile than hard disks and are also silent (unless a cooling fan is used); as there are no mechanical delays, they usually enjoy low access time and latency.
Advantages
- Faster start-up, as no spin-up is required (RAM & flash).
- Typically fast random access for reading, as there is no read/write head to move (RAM & flash).
- Extremely low read latency times, as SSD seek-times are orders of magnitude lower than the best hard disk drives, as of 2008.(RAM) In applications where hard disk seeks are the limiting factor, this results in faster boot and application launch times (see Amdahl's law)
- Relatively deterministic read performance
- unlike hard disk drives, performance of SSDs is almost constant and deterministic across the entire storage. This is because the seek time is almost instant and does not depend on the physical location of the data, and so, file fragmentation has almost no impact on read performance.
- No noise: a lack of moving parts makes SSDs completely silent, apart from cooling fans on a few high-end and high-capacity SSDs.
- For low-capacity flash SSDs, low power consumption and heat production when in active use, although high-end SSDs and DRAM-based SSDs may have significantly higher power requirements (flash).
- High mechanical reliability, as the lack of moving parts almost eliminates the risk of "mechanical" failure (RAM & flash).
- Ability to endure extreme shock, high altitude, vibration and extremes of temperature: once again because there are no moving parts.This makes SSDs useful for laptops, mobile computers, and devices that operate in extreme conditions (flash).
- Larger range of operating temperatures. Typical hard drives have an operating range of 5-55 degrees C. Most flash drives can operate at 70 degrees, and some industrial grade drives can operate over an even wider temperature range.
- For low-capacity SSDs, lower weight and size: although size and weight per unit storage are still better for traditional hard drives, and microdrives allow up to 20 GB storage in a CompactFlash 42.8×36.4×5 mm (1.7×1.4×.2 in) form-factor. Up to 256 GB, as of 2008 SSDs are lighter than hard drives of the same capacity.
- When failures occur, they tend to happen predominantly while writing, or erasing cells, rather than upon reading cells. With magneto-mechanical drives, failures tend to occur while reading. If a drive detects failure on write operations, data can be written to a new location. If a drive fails on read, then data is usually lost permanently.
Disadvantages
- Cost: SSD prices are still considerably higher per gigabyte than are comparable conventional hard drives: consumer-grade drives are typically US$1.50 to US$3.45 per GB for flash drives and over US$10.00 per GB for RAM-based compared to about US$0.38 or less per gigabyte for hard drives.
- * Capacity: As of 2008, far lower than that of conventional hard drives (Flash SSD capacity is predicted to increase rapidly, with experimental drives of 1 TB,[30][31] but hard drive capacity also continues to expand, and hard drives are likely to maintain their capacity edge for some time).[32]
- * Asymmetric Read vs. Write Performance: Unlike other architectural elements in the memory hierarchy, storage devices based on NAND Flash memory suffer from write performance that is typically two orders of magnitude slower than read performance. Many computer applications rely on synchronous patterns of read/write operations, wherein a given write or update must be completed and the write confirmed before additional application read requests can be issued. These include transaction processing applications, computer operating system "boot-up" and even basic forms of parity-based RAID. For these applications a Flash SSD can actually be slower than a hard disk drive, due to the inability of applications to place subsequent read-requests into the device queue until previous write operations have been completed and acknowledged.[33]
- * Lower storage density: Hard disks can store more data per unit volume than DRAM or flash SSDs, except for very low capacity/small devices.
- * Limited write (erase) cycles: Flash-memory cells will often wear out after 1,000 to 10,000 write cycles for MLC, and up to 100,000 write cycles for SLC[18], while high endurance cells may have an endurance of 1–5 million write cycles (many log files, file allocation tables, and other commonly used parts of the file system exceed this over the lifetime of a computer).[34][35][36] Special file systems or firmware designs can mitigate this problem by spreading writes over the entire device (so-called wear leveling), rather than rewriting files in place.[37] In 2008 wear leveling was just beginning to be incorporated into consumer level devices.[18] However, effective write cycles can be much less, because when a write request is made to a particular memory block, all data in the block is overwritten even when only part of the memory is altered. The write amplification, as referred by Intel, can be reduced using write memory buffer.[38] In combination with wear leveling, over-provisioning SSD flash drives with spared memory capacity also delays the loss of user-accessible memory capacity. NAND memory can be negatively impacted by read and program (write) disturbs arising from over accessing a particular NAND location. This overuse of NAND locations causes bits within the NAND block to erroneously change values. Wear leveling, by redirecting SSD writes to lesser-used NAND locations, thus reduces the potential for program or write disturbs.[39] An example for the lifetime of SSD is explained in detail in this wiki.[dubious – discuss] SSDs based on DRAM, however, do not suffer from this problem.
- As a result of wear leveling and write combining, the performance of SSDs degrades with use . Eventually, wear leveling will use each page on the drive at least once, so further writes always involve a block erase. Although write combining (if supported by the device) offers advantages, it causes internal fragmentation in the SSD which degrades the sequential read speed. However, such fragmentation can be mitigated by the operating system, using the TRIM command.
from : http://en.wikipedia.org/wiki/Solid_state_drive
Settings Shortlist for SSD's:
- Alignment: Yes
- Defragmentation : No disable
- Indexing : No disable
- Swapfile on SSD: Yes
- Let 10% of your SSD space untouched: your choice
- Raidcontroller: your choice
- Cachingsoftware: Yes, If using Micron
- Superfetch :No disable
Populair SSD's :
Must Read:
OCZ Vertex
Intel X-25M
Intel X-25M
Must Read:
Alignment and why it's important
The SSD Relapse: Understanding and Choosing the Best SSD
Benchmarks
My OCZ Vertex 30GB in Raid0 :
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